Capsule containing beverage powder, in particular for preparing brewed coffee

ABSTRACT

A capsule, especially for preparing a beverage from beverage powder, in particular of coffee from coffee powder, by introducing water into the capsule, wherein the capsule comprises a compacted pellet made of a powder containing at least one polysaccharide, wherein the compacted pellet is sheathed with at least one coating layer, wherein the at least one coating layer comprises a cross-linked polysaccharide, wherein the cross-linked polysaccharide can be obtained by cross-linking a polysaccharide with a cross-linking agent without the use of a polyol spacer. 
     A method for manufacturing such a capsule comprises the following steps:
         i) preparing a compacted pellet from a powder containing at least one polysaccharide,   ii) bringing at least one part and preferably the entire surface of the compacted pellet used in step i) into contact with a solution of a polysaccharide in a solvent or with a dispersion of a polysaccharide in a dispersant,   iii) when appropriate, removing of the compacted pellet from the solution or dispersion of step ii),   iv) bringing the compacted pellet obtained in step ii) or iii) into contact with at least one cross-linking agent,   v) when appropriate, removing the compacted pellet from the solution of step iv) and   vi) drying of the compacted pellet obtained in step iv) or v).

The present invention relates to a capsule containing a beverage powder,which is particularly suitable for the preparation of a beverage, suchas cocoa, tea or coffee.

Over the past few years, coffee capsules, besides coffee pads, have beenused increasingly in the portion-wise preparation of beverages, inparticular brewed coffee; the capsule walls are usually made ofstainless steel, aluminium or plastic. Such capsules enable the storageof coffee powder for a fairly long period of time without loss offlavour. In addition, such capsules enable fast and user-friendlyproduction of a portion of coffee with the desired flavour, in that acapsule containing the desired type of coffee is placed in a coffeemachine adapted for this purpose, in which hot water is then pressedthrough the capsule, from which the desired brewed coffee is produced.However, such capsules are comparatively expensive because of thecapsule material used and the production-intensive capsule construction.Furthermore, such capsules are environmentally problematic. The capsulesare not recyclable, and the user usually disposes of them as residualwaste. Recycling of coffee capsules therefore practically does not takeplace, which is particularly concerning in the case of aluminium-basedcoffee capsules, since the production of aluminium is veryenergy-intensive, resulting in such capsules having a particularly poorCO₂ balance. Another major disadvantage is that such capsules are notbiodegradable and therefore cannot be disposed of biologically.Considering the fact that in Germany alone more than 2 billion coffeecapsules are used annually, this is a very serious problem.

To at least partially overcome the above problems, capsules made ofalternative materials have already been proposed.

For example, capsules are known from WO 2010/006979 A1 that are filledwith coffee or tea in their interior and comprise a capsule wall, whichin addition to the capsule contents also contains water as a structuringcomponent. For the formation of a stable capsule wall, however, it isnecessary that the capsule be cooled below the freezing point of thestructuring component, because the structuring component melts when itsfreezing point is exceeded and moistens the capsule contents. Naturally,this restricts the use of such capsules considerably.

WO 2009/053811 A2 describes a capsule which can contain ground coffee,cappuccino powder, chocolate powder, milk powder or tea powder. Thecapsule consists of two half shells, which form the capsule walls. Thecapsule walls consist of a water-soluble material which dissolves duringthe brewing process. In this concept, the capsule wall materialdissolves during the brewing process and thus becomes part of theprepared drink, which may undesirably affect the taste. Apart from that,the production of such capsules is complicated and expensive.

Taking this as the point of departure, the present invention is based onthe objective of providing a capsule for the portion-by-portionpreparation of beverages from beverage powder, such as cocoa, tea andcoffee, which can not only be produced in a simple and cost-effectivemanner, but which, in particular, is also biodegradable and cantherefore be disposed of in an environmentally friendly manner; thecapsule can also be stored over a long period of time without anyappreciable loss of flavour and can be used in correspondingly designedbeverage vending machines.

According to the invention, this objective is achieved by a capsule,wherein the capsule comprises a compacted pellet of a powder containingat least one polysaccharide, such as in particular coffee powder,wherein the compacted pellet is sheathed with at least one coatinglayer, with the at least one coating layer comprising a cross-linkedpolysaccharide, wherein the cross-linked polysaccharide has been or canbe obtained by the cross-linking of a polysaccharide with across-linking agent without the use of a polyol separator or polyolspacer.

This solution is based on the recognition that such a capsule consistingof a compacted pellet composed of a powder containing at least onepolysaccharide, such as coffee powder, wherein the compacted pellet issheathed by at least one coating layer composed of a cross-linkedpolysaccharide, not only exhibits all the necessary properties which arerequired for the use thereof in the portion-by-portion preparation ofbeverages, such as coffee, but in particular can also be disposed of inan environmentally friendly manner. In particular, the at least onecoating layer composed of a cross-linked polysaccharide is stable enoughto provide the capsule with sufficiently high transport protection, aswell as handling protection. Apart from that, according to theinvention, the capsule also protects the capsule content over aprolonged period of time without a noticeable loss of flavour. This isbased on a synergistic cooperation of the at least one coating layercomposed of cross-linked polysaccharide and the compacted pellet. Thepressing of the coffee powder into a compacted pellet means that thesurface area of the coffee powder which is accessible to oxygen issignificantly reduced compared to powder in a not compacted form. Inaddition, the sheathing composed of a cross-linked polysaccharidefunctions as a further oxygen barrier. The combination of the reducedsurface area and the sheathing thus results in preservation of theflavour of the capsule content. A further advantage of the capsuleaccording to the invention consists in the fact that the at least onecoating layer does not dissolve during the preparation of the beverageand consequently does not cause any adulteration of the taste of theprepared beverage. Aside from this, the capsule according to theinvention can be produced in a simple and cost-effective manner. Inaddition, the capsule according to the invention can easily be producedin a spherical form and is thus excellently suited for use in acorrespondingly adapted automatic beverage vending machine, because itcan roll. Moreover, of particular importance is that the at least onecross-linked polysaccharide coating is completely biodegradable and cantherefore be disposed of in an environmentally friendly manner. Becausepolysaccharides are not of fossil origin and their production iscomparatively less energy intensive, the capsule according to theinvention exhibits an advantageous CO₂ balance.

In principle, the present invention is not limited with regard to thechemical nature of the polysaccharide of the at least one coating layer.Good results are obtained when the polysaccharide of the at least onecoating layer is selected from the group consisting of starch,cellulose, chitin, carrageenan, agar and alginates. Particularlypreferred would be for the polysaccharide of the at least one coatinglayer to comprise a carrageenan or an alginate, whereby it is moreparticularly preferred that the polysaccharide of the at least onecoating layer is an alginate. In the context of the present invention,it has been found that these polysaccharides do not cause anyadulteration of the taste during the preparation of the beverage. In thecontext of the present invention, it has also been found that compactedpellets, in particular those composed of coffee powders, can easily besheathed with alginate in a cost-effective manner. Alginates arebiodegradable and provide a sufficiently stable sheathing and protectionfor the contents of the capsule without a significant loss of flavour.In the context of the present invention, it has also been found thatalginates are able to reduce water hardness. An unpleasant acid taste isthereby lessened.

It is essential to the invention that the polysaccharide of the at leastone coating layer is cross-linked. According to one embodiment of thepresent invention, the polysaccharide can be cross-linked via covalentbonds. Cross-linking via covalent bonds enables very durable sheathings.At the same time, cross-linking via covalent bonds usually takes placethrough the reaction of the polysaccharide with a suitable cross-linkingagent. Particularly suitable cross-linking agents are difunctionalorganic compounds, wherein the functional groups are selected, forexample, from the group that consists of carboxylic acids, salts ofcarboxylic acids, activated carboxylic acids, amines, alcohols,aldehydes and ketones. In this context, activated carboxylic acids arecarboxylic acid halides, active esters of carboxylic acids, anhydridesof carboxylic acids or other reactive derivatives of carboxylic acids.Preferably, the cross-linking is carried out without the use of a spacerand, particularly, without a polyol spacer.

According to an alternative and particularly preferred embodiment of thepresent invention, the polysaccharide of the at least one coating layeris cross-linked via ionic and/or coordinative bonds. Suchpolysaccharides cross-linked via ionic and/or coordinative bonds can beproduced in a particularly easy manner and do not impair thebiodegradability of the polysaccharide used. The ionic and/orcoordinative cross-linking can be achieved, for example, by means ofpolysaccharides which have anionic groups such as carboxylate groups orsulfonate groups. By introducing divalent or higher-valent cations, inparticular alkaline earth metal ions, ionic or coordinativecross-linking of the anionic groups of the polysaccharide then takesplace in order to form a stable sheathing layer.

In this context, a coordinative bond denotes an interaction between anelectron pair donor and an electron pair acceptor, for example, such ascan take place between free electron pairs of oxygen atoms in hydroxylgroups and cations.

More particularly preferred, in the case of the cross-linkedpolysaccharide, would be an alkaline earth metal alginate, and maximallypreferred would be a calcium alginate. In this case, the calcium ionsare the cross-linkers because they enter into coordinative or ionicbonds with groups of the alginate. In the context of the presentinvention, it has surprisingly been found that a sheathing comprisingcalcium alginate provides a water-insoluble layer which does not impairthe taste of the beverage produced from the capsule and providessufficient stability of the capsule in order to ensure protection duringtransport and handling without the capsule contents suffering asignificant loss of flavour. Moreover, calcium alginate is excellentlybiodegradable. A further advantage is that calcium alginate is anapproved food additive with the E-number E405 and is therefore harmlessto health. It is additionally preferred in this embodiment that thecontent of the capsule, that is to say the compacted pellet composed ofpolysaccharide, is at least substantially free of alkaline earth metalions and in particular calcium ions, by which is meant that thecompacted pellet, except for the polysaccharide of which the compactedpellet is made and which might contain natural alkaline earth metal ionsand in particular calcium ions, shall contain no further alkaline earthmetal ions and in particular no calcium ions. It is particularlypreferred that the compact pellet contained in the capsule or at least80% of the internal volume of the compacted pellet should have analkaline earth metal ion concentration and in particular a calcium ionconcentration of less than 1 mol/l; less than 0.1 mol/l is preferred;even more preferred is less than 0.001 mol/l and particularly preferredis less than 0.001 mol/l; more particularly preferred would be less than0.0001 mol/l and maximally preferred would be less than 0.00001 mol/l.“80% of the internal volume of the compacted pellet” is understood tomean the volume which is obtained when a spherical surface is spannedfrom the longest section leading radially from the centre point to theouter surface of the compacted pellet around the point lying at 80%starting from the centre point to the outer surface point. Contaminationof the compacted pellet with alkaline earth metal ions and in particularcalcium ions can be prevented in that the alkaline earth metal ions andin particular calcium alginate coating are produced in that thecompacted pellet is first contacted with the alkali metal alginatesolution and only thereafter, during the formation of the calciumalginate coating, with a liquid containing alkaline earth metal ions andespecially calcium ions, and is not first contacted with a fluidcontaining an earth metal alginate and particularly calcium ions beforean alkali metal alginate solution is added.

In principle, the capsule according to the invention can comprise only acoating layer of cross-linked polysaccharide. In order to increase thestability of the capsule and thus the transport safety and the handlingprotection, it is proposed in a further development of the inventiveconcept that the capsule according to the invention should comprise twoor more coating layers. Preferably, the compacted pellet of the capsuleis to be sheathed with 2 to 100 coating layers; particularly preferredwould be 2 to 20 and more particularly preferred would be 2 to 10 andmaximally preferred would be 2 to 5 coating layers. The sheathing of thecompacted pellet of the capsule with two or more coating layers alsoincreases the effect of the coating as an oxygen barrier as well as theresulting provision of effective aroma protection to a particularly highdegree.

It has been found that the first coating layer penetrates as a gel intothe still rough surface of the compacted pellet and leads to a smoothersurface. This means a further surface area reduction, which enhances theflavour density further. An even smoother surface is then achieved withfurther coating layers, and this also exhibits the necessary stability,so that even harder shocks can be absorbed without a damaging effect.

According to a further, particularly preferred embodiment of the presentinvention, the coating of the capsule consists of 2 to 100 calciumalginate coating layers; preferred would be 2 to 20, particularlypreferred would be 2 to 10 and highly preferred would be 2 to 5 layerswith which the compacted pellet is to be sheathed.

The individual coating layers feature, depending on the viscosity of thesodium alginate and the procedure followed, thickness ranging between 50and 600 μm. Particularly preferred would be layer thicknesses of up to100 to 300 μm for the first coating layer, since they exhibit theoptimum compromise between stability and drying speed. Subsequentcoating layers are preferably thinner and are preferably between 50 and200 microns thick to enable rapid drying.

A thin coating layer is preferred in order to remove the water containedin the gel more easily, and to facilitate the fastest possible diffusionof the cross-linking agent, that is the calcium ions, into the sodiumalginate. In principle, the rate of diffusion of the calcium ions intothe sodium alginate can also be increased with a higher concentration ofthe cross-linking agent; however, in the practical implementation ofthis variant, thin coating thicknesses have proven to be advantageousfor the speed of the diffusion and handling.

The present invention is not particularly limited with regard to thematerial from which the compacted pellet of the capsule according to theinvention is made. Good results are obtained when the compacted pelletcontains or preferably is composed of or consists of a material which isselected from the group consisting of coffee, tea, drinking chocolate,cocoa and milk powder. Good results are obtained in particular when thecompacted pellet consists of ground coffee powder.

In the context of the present invention, a compacted pellet isunderstood to mean compressed powder. Good results are obtained, inparticular, if the compacted pellet of the capsule according to theinvention is made by pressing powder, in particular coffee powder, witha pressure of 0.01 to 1000 MPa, preferably 0.05 to 500 MPa, particularlypreferably 0.1 to 100 MPa, even more preferably 0.5 to 100 MPa, stillmore preferably 1 to 100 MPa, more particularly preferably 5 to 50 MPa,and most preferably 15 to 30 MPa. In this manner, sufficient compressioncan be provided for secure sheathing of the compacted pellet, and a goodoxygen barrier can be achieved. At lower pressures, there is nosufficient cohesion and at higher pressures too strong cohesion occurs,which under some circumstances becomes relaxed after removal from thepress, possibly leading to the destruction of the capsules.

The present invention further relates to a capsule which comprises acompacted pellet made from a powder of a substance selected from thegroup consisting of coffee, tea, drinking chocolate, cocoa and milkpowder, wherein the compacted pellet is obtained by pressing the powderat a pressure of 0.01 to 1.000 MPa, preferably 0.05 to 500 MPa,particularly preferably 0.1 to 100 MPa, further preferably 0.5 to 100MPa, still more preferably 1 to 100 MPa, more particularly preferably 5to 50 MPa and most preferably 15 to 30 MPa, and wherein the compactedpellet is sheathed with 1 to 100, preferably with 2 to 20, particularlypreferably with 2 to 10 and maximally preferably with 2 to 5 coatinglayers of calcium alginate. Maximally preferred is when the capsule,according to the invention, consists of a compacted pellet obtained froma powder of a substance selected from the group consisting of coffee,tea, drinking chocolate, cocoa and milk powder with a pressure of 15 to30 MPa, and wherein the compacted pellet is sheathed with 2 to 20coating layers of calcium alginate.

In principle, the compacted pellet can have any shape, for example, theshape of a truncated cone, cone, ellipsoid, cylinder, cuboid, a coffeebean or a sphere. The capsule according to the invention, particularlypreferably has the shape of a sphere, since the ratio of surface tovolume is lowest in this case, as a result of which the aroma isparticularly well preserved. In addition, the spherical shape allows thecapsule to roll and therefore to be used particularly well in a beveragevending machine.

The present invention further relates to a method for producing acapsule which comprises the following steps:

-   i) preparing a compacted pellet from a powder containing at least    one polysaccharide,-   ii) bringing at least part of the surface and preferably the entire    surface of the compacted pellet used in step i) into contact with a    solution of a polysaccharide in a solvent or with a dispersion of a    polysaccharide in a dispersant,-   iii) when appropriate, removing of the compacted pellet from the    solution or dispersion of step ii),-   iv) bringing the compacted pellet obtained in step ii) or iii) into    contact with at least one cross-linking agent,-   v) when appropriate, removing the compacted pellet from the solution    of step iv) and-   vi) drying of the compacted pellet obtained in step iv) or v).

The bringing into contact of the compacted pellet in step ii) ispreferably carried out in such a way that at least a part of the surfaceand preferably the entire surface of the compacted pellet is wetted withthe solution or dispersion of the polysaccharide. For example, thecontacting of the compacted pellet in steps ii) and iv) is carried outindependently of one another by immersion, spraying or coating of thecompacted pellet with the solution or dispersion of the polysaccharideor with the cross-linking agents.

The method according to the invention makes it possible to sheath thecompacted pellet evenly. Particularly even when the compacted pellet isspherical, without creating an edge or a seam.

The solvent or dispersant is preferably a water-based solvent ordispersant. Water is particularly preferred as the solvent ordispersant.

The compacted pellet in step ii) is preferably immersed in or sprayedwith an aqueous 0.5 to 5 wt % alkali metal alginate solution.Particularly preferred is to immerse or spray the compacted pellet instep ii) with an aqueous 1 to 2 wt % alkali metal alginate solution. Ata concentration of less than 0.5 wt %, the alkali metal alginatesolution is not concentrated enough and is too low in viscosity to applya sufficient amount of alkali metal alginate to the compacted pellet bysimple dipping or spraying in order to produce a sufficiently stablesheathing in the following steps. If the concentration of the alkalimetal alginate exceeds 5 wt %, the viscosity of the alkali metalalginate solution is so high that the formation of a full sheathing isimpeded. In addition, the coating thicknesses increase at aconcentration of the alkali metal alginate of over 5 wt %. so thatdrying becomes more difficult.

The alkali metal alginate solution is preferably a solution of a salt,which consists of alginate and a cation of an alkali metal or a relatedcation such as, for example, an ammonium ion. Particularly preferably,the alkali metal alginate solution is an aqueous solution of sodiumalginate, potassium alginate or ammonium alginate. Sodium alginate,potassium alginate and ammonium alginate are approved food additiveswith E-numbers E401, E402 or E403. Such sheathings can be used withouthesitation in the food industry. More particularly preferred is anaqueous solution of sodium alginate.

In the method of the present invention, it is preferred to immerse or tospray the compacted pellet in step iv) in/with an aqueous 1 to 15 wt %,preferably 1 to 7 wt %, alkaline earth metal salt solution. In the caseof an alkaline earth metal salt concentration between 1 and 15 wt %,preferably between 1 and 7 wt %, rapid ionic cross-linking of thepolysaccharide can be achieved. The alkaline earth metal salt ispreferably a calcium salt, such as calcium chloride in particular.

Because the compacted pellet is first contacted with an alkali metalalginate solution and is only thereafter contacted with a liquidcontaining alkaline earth metal ions and, in particular, calcium ions,under formation of the coating containing alkaline earth metal ions and,in particular, a calcium alginate, it is achieved that the compactedpellet composed of polysaccharide in the capsule is at leastsubstantially free of alkaline earth metal ions and in particularcalcium ions. This is understood to mean that the compacted pelletcontained in the capsule contains no further alkaline earth metal ionsand in particular calcium ions apart from the naturally containedalkaline earth metal ions and in particular calcium ions possiblypresent in the polysaccharide from which the compacted pellet was made.It is particularly preferred that the compact pellet contained in thecapsule or at least 80% of the internal volume of the compacted pelletshould have an alkaline earth metal ion concentration and in particulara calcium ion concentration of less than 1 mol/l; less than 0.1 mol/l ispreferred; even more preferred is less than 0.001 mol/l and particularlypreferred is less than 0.001 mol/l; more particularly preferred would beless than 0.0001 mol/l and maximally preferred would be less than0.00001 mol/l. “80% of the internal volume of the compacted pellet” isunderstood to mean the volume which is obtained when a spherical surfaceis spanned from the longest section leading radially from the centrepoint to the outer surface of the compacted pellet around the pointlying at 80% starting from the centre point to the outer surface point.

In order to encapsulate a compacted pellet with several layers, stepsii) to v) or steps ii) to vi) can be repeated several times, namelypreferably 2 to 20 times and particularly preferably 2 to 10 times andmaximally preferably 2 to 5 times.

Drying in step vi) can be carried out in different ways, whereby variousdrying methods have proved to be successful. A very even drying can beachieved, although not exclusively, through drying in a stream of air insuitable channels, wherein the compacted pellet floats freely and driesevenly by its own rotation. To better absorb the water that diffuses outthrough the coating layer during its formation, contact drying onabsorbent or warm surfaces has also proven to be useful. Both principlescan be combined in a type of fluidized bed channel. Infrared dryers andmicrowave dryers can also be used as other very efficient dryingprinciples.

The present invention further relates to the use of the capsuleaccording to the invention for producing a beverage by bringing thecapsule according to the invention into contact with water. Preferably,the capsule contains a material which is selected from the groupconsisting of coffee, tea, drinking chocolate, cocoa and milk powder.

The use of the capsule according to the invention for the preparation ofa coffee beverage allows the portion-by-portion preparation of thebeverage depending on the needs as required. A particular advantage ofthe application according to the invention is that only biodegradablewaste is produced.

When using the capsule according to the invention for preparing abeverage, in particular a coffee beverage, the coffee capsules arepreferably crushed or perforated before the extraction of the crushed orperforated coffee capsule with water takes place.

Hereinafter, the present invention will be explained on the basis of twoexamples which are meant to illustrate but are non-limiting.

EXAMPLE 1

8 g of ground roasted coffee were pressed into a spherical compactedpellet with a press at a pressure of 20 MPa. The resulting sphericalcompacted pellet was then immersed in a 1 wt % aqueous sodium alginatesolution and after 1 to 2 seconds, removed from the sodium alginatesolution. After removal of the compacted pellet from the sodium alginatesolution, it was sprayed with a 5 wt % CDCl₂ solution. Then, thecompacted pellet was dried for 10 minutes at room temperature in astream of air.

A capsule consisting of a compacted pellet with an encapsulated layer ofcalcium alginate was obtained.

EXAMPLE 2

A coffee capsule was prepared as in Example 1, except that the steps ofimmersing the compacted pellet in the sodium alginate solution, removingfrom the sodium alginate solution, spraying with the calcium chloridesolution and drying are to be repeated successively for a total of 5times each.

A capsule consisting of a compacted pellet with five encapsulated layersof calcium alginate was obtained.

1. A capsule for preparing a beverage from beverage powder byintroducing water into the capsule, wherein the capsule comprises acompacted pellet made of a powder containing at least onepolysaccharide, wherein the compacted pellet is sheathed with at leastone coating layer, wherein the at least one coating layer comprises across-linked polysaccharide, wherein the cross-linked polysaccharide isobtainable by cross-linking the polysaccharide with a cross-linkingagent without the use of a polyol spacer.
 2. The capsule according toclaim 1, wherein the polysaccharide of the at least one coating layer isselected from the group consisting of starch, cellulose, chitin,carrageenan, agar and alginates.
 3. The capsule according to claim 2,wherein the polysaccharide of the at least one coating layer is analginate.
 4. The capsule according to claim 1, wherein thepolysaccharide of the at least one coating layer is cross-linked viacovalent bonds.
 5. The capsule according to claim 1, wherein thepolysaccharide of the at least one coating layer is cross-linked viaionic and/or coordinative bonds.
 6. The capsule according to claim 5,wherein the cross-linked polysaccharide of the at least one coatinglayer is an alkaline earth metal alginate.
 7. The capsule according toclaim 1, wherein the compacted pellet is sheathed with 1 to 100 coatinglayers.
 8. The capsule according to claim 3, the compacted pellet issheathed with 2 to 100 coating layers of calcium alginate.
 9. Thecapsule according to claim 1, wherein the compacted pellet contains amaterial selected from the group consisting of coffee, tea, drinkingchocolate, cocoa and milk powder.
 10. The capsule according to claim 1,wherein the compacted pellet can be obtained by pressing the powder witha pressure of 0.01 to 1000 MPa.
 11. The capsule according to claim 1,wherein the capsule comprises a compacted pellet made from a powder of asubstance selected from the group consisting of coffee, tea, drinkingchocolate, cocoa and milk powder, wherein the compacted pellet isobtained by pressing the powder at a pressure of 0.01 to 1.000 MPa andwherein the compacted pellet is encapsulated with 1 to 100 coatinglayers of calcium alginate.
 12. A method for manufacturing a capsuleaccording to claim 1, comprising the following steps: i) preparing acompacted pellet from a powder containing at least one polysaccharide,ii) bringing at least one part of the compacted pellet used in step i)into contact with a solution of a polysaccharide in a solvent or with adispersion of a polysaccharide in a dispersant, iii) when appropriate,removing of the compacted pellet from the solution or dispersion of stepii), iv) bringing the compacted pellet obtained in step ii) or iii) intocontact with at least one cross-linking agent, v) when appropriate,removing the compacted pellet from the solution of step iv) and vi)drying of the compacted pellet obtained in step iv) or v).
 13. Themethod according to claim 12, in which the compacted pellet in step ii)is dipped in or sprayed with an alkali metal alginate solution.
 14. Themethod according to claim 12 wherein the compacted pellet in step iv) isdipped in or sprayed with an alkaline earth metal salt solution. 15.(canceled)
 16. The capsule according to claim 6, wherein the alkalineearth metal alginate is a calcium alginate.
 17. The method according toclaim 13, wherein the alkali metal alginate solution is an aqueous 0.5to 5 wt. % alkali metal alginate solution.
 18. The method according toclaim 17, wherein the alkali metal alginate solution is an aqueous 0.5to 5 wt. % sodium alginate solution.
 19. The method according to claim14, wherein the alkaline earth metal salt solution is an aqueous 1 to 7wt. % alkaline earth metal salt solution.
 20. The method according toclaim 19, wherein the alkaline earth metal salt solution is an aqueous 1to 7 wt. % calcium chloride solution.